Added MultipleWindows platform capability.

Several platform plugins, like eglfs, kms, etc don't support multiple
windows as there's no system compositor, they're rendering directly to
a single back buffer. By adding a platform capability we'll be able to
provide better error reporting when an application tries to create
multiple QWindows on a single-window platform. Also, QML apps can use
this capability to figure out whether they should create a QWindow for
dialogs / popups / menus, or whether to just create items in the same
scene, that are shown on top of the rest of the content.

Change-Id: I15b8d21ee2bc4568e9d705dbf32f872c2c25742b
Reviewed-by: Andy Nichols <andy.nichols@digia.com>

4 files changed, 5 insertions, 0 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoaintegration.mm b/src/plugins/platforms/cocoa/qcocoaintegration.mm
index 2fdb367c62..481055aae4 100644
--- a/src/plugins/platforms/cocoa/qcocoaintegration.mm
+++ b/src/plugins/platforms/cocoa/qcocoaintegration.mm
@@ -309,6 +309,7 @@ bool QCocoaIntegration::hasCapability(QPlatformIntegration::Capability cap) cons
     case ThreadedOpenGL:
     case BufferQueueingOpenGL:
     case WindowMasks:
+    case MultipleWindows:
         return true;
     default:
         return QPlatformIntegration::hasCapability(cap);
diff --git a/src/plugins/platforms/minimal/qminimalintegration.cpp b/src/plugins/platforms/minimal/qminimalintegration.cpp
index 6a2db91e34..e9fab6d87c 100644
--- a/src/plugins/platforms/minimal/qminimalintegration.cpp
+++ b/src/plugins/platforms/minimal/qminimalintegration.cpp
@@ -74,6 +74,7 @@ bool QMinimalIntegration::hasCapability(QPlatformIntegration::Capability cap) co
 {
     switch (cap) {
     case ThreadedPixmaps: return true;
+    case MultipleWindows: return true;
     default: return QPlatformIntegration::hasCapability(cap);
     }
 }
diff --git a/src/plugins/platforms/windows/qwindowsintegration.cpp b/src/plugins/platforms/windows/qwindowsintegration.cpp
index 3f030ffca7..a02f0cd494 100644
--- a/src/plugins/platforms/windows/qwindowsintegration.cpp
+++ b/src/plugins/platforms/windows/qwindowsintegration.cpp
@@ -338,6 +338,8 @@ bool QWindowsIntegration::hasCapability(QPlatformIntegration::Capability cap) co
 #endif // !QT_NO_OPENGL
     case WindowMasks:
         return true;
+    case MultipleWindows:
+        return true;
     default:
         return QPlatformIntegration::hasCapability(cap);
     }
diff --git a/src/plugins/platforms/xcb/qxcbintegration.cpp b/src/plugins/platforms/xcb/qxcbintegration.cpp
index a46d51127f..2ffe53c04b 100644
--- a/src/plugins/platforms/xcb/qxcbintegration.cpp
+++ b/src/plugins/platforms/xcb/qxcbintegration.cpp
@@ -216,6 +216,7 @@ bool QXcbIntegration::hasCapability(QPlatformIntegration::Capability cap) const
 #endif
     case ThreadedOpenGL: return false;
     case WindowMasks: return true;
+    case MultipleWindows: return true;
     default: return QPlatformIntegration::hasCapability(cap);
     }
 }